---
canonical: 'https://htmlcsstoimage.com/features/html-to-png/curl'
title: 'Convert HTML to PNG in cURL | HTML/CSS to Image'
description: 'Convert HTML and CSS to PNG in cURL. Generate a hosted .png image URL.'
---

# Generate PNG images in cURL without managing Chrome

Render HTML and CSS from cURL without installing Chrome, running a local browser process, or building a separate image-storage pipeline.

## Why use the API instead of native cURL browser automation?

- Use HCTI from shell scripts and automation without installing a browser or maintaining a browser-control program.
- Use managed browser versions, isolated render jobs, timing controls, and consistent viewport behavior across deployments.
- Receive a hosted .png URL without building a separate pipeline for temporary files, uploads, storage, and delivery.

## Complete cURL request

Use this request to render the example HTML and CSS as PNG.

```bash
curl --fail-with-body --request POST 'https://hcti.io/v1/image' \
  --user "$HCTI_API_ID:$HCTI_API_KEY" \
  --data-urlencode 'html=<div class="card">
  <h1>Hello, world!</h1>
  <p>Generated from HTML and CSS.</p>
</div>' \
  --data-urlencode 'css=.card {
  width: 480px;
  padding: 40px;
  background: #f0fdf4;
  color: #052e16;
  font-family: sans-serif;
}' \
  --data-urlencode 'format=png'

```

## When to use PNG

PNG preserves sharp edges, text, and transparency, making it ideal for interface captures and designed graphics.

- **Lossless detail**: Keep text, icons, charts, and interface elements crisp without compression artifacts.
- **Transparent backgrounds**: Preserve transparent HTML backgrounds for overlays, product graphics, badges, and reusable assets.
- **Reliable visual fidelity**: Use PNG when exact colors and sharp edges matter more than achieving the smallest possible file.

## API request

Send an authenticated `POST` request to `https://hcti.io/v1/image`. Include `html`, optional `css`, `format`, and any viewport or browser options required by the render.

```json
{
  "html": "\u003Carticle class=\u0027card\u0027\u003E...\u003C/article\u003E",
  "css": ".card { display: grid; width: 1200px; }",
  "format": "png",
  "viewport_width": 1200,
  "viewport_height": 630
}
```

## Request workflow

1. **Send HTML and CSS** — Submit the content with format set to png and any viewport or browser settings.
2. **Chromium renders the design** — The API loads the markup, styles, fonts, and assets in a managed browser environment.
3. **Use the .png URL** — Embed the hosted result, download the file, or save it in your own storage and application records.

## Authentication and output handling

- Authenticate from trusted server-side code. Do not expose an API key in browser JavaScript, generated HTML, logs, or agent-visible output.
- Treat the returned URL as the generated `png` resource. Download it, embed it, or copy it to configured storage as required by the workflow.
- Use viewport, selector, timing, and browser options when the default capture does not match the required dimensions or page state.
- If credentials are unavailable, ask the user to configure them securely before attempting an API request.

## Use through MCP

An MCP-compatible agent can connect to `https://mcp.hcti.io` with OAuth and use the connected HTML/CSS to Image account instead of handling an API key directly.

Ask the MCP tool to render the supplied HTML and CSS as PNG, or specify `format: png` explicitly when constructing the request.

- [Read the MCP integration documentation](https://docs.htmlcsstoimage.com/integrations/mcp/)

## Related conversions

- [URL to PNG](https://htmlcsstoimage.com/features/url-to-png/curl.md): Capture a public webpage as PNG instead of supplying HTML and CSS.
- [HTML to JPEG](https://htmlcsstoimage.com/features/html-to-jpeg/curl.md): JPEG is a practical choice for photographic and content-rich images where broad compatibility and smaller files matter.
- [HTML to WebP](https://htmlcsstoimage.com/features/html-to-webp/curl.md): WebP combines modern compression with high visual quality, making it a strong default for images delivered on the web.
- [HTML to PDF](https://htmlcsstoimage.com/features/html-to-pdf.md): Generate paginated documents with page sizing, margins, backgrounds, and print styles.

## Reference links

- [API authentication and request documentation](https://docs.htmlcsstoimage.com/getting-started/using-the-api/)
- [MCP integration documentation](https://docs.htmlcsstoimage.com/integrations/mcp/)
- [Interactive HTML to PNG page](https://htmlcsstoimage.com/features/html-to-png/curl)
- [Plans and current limits](https://htmlcsstoimage.com/pricing.md)